Method of renovating waste



Sept. 13, 1932.

E. S. PEARCE METHOD OF RENOVATING WASTE Filed June 8, 1928 5 Sheets-Sheet INVENTOR ATTORNEY 5 Sheets-Sheet 2 o n o i o an no. on

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INVENTOR ATTORNEY$ Sept. 13, 1932. E. s. PEARCE METHOD OF RENOVATING WASTE Filed June 8, 1928 Spt. 13, 1932. I E, PEARCE 1,877,754

METHOD 0F RENOVATING WASTE Filed June 8, 1928 5 Sheets-Sheet 3 J I INVENTOR I Y ATTORNEYS Patented Sept. 13, 1932 I UNITED STATES PATENT OFFICE EDWIN S. PEARCE, OF INDIANAPOLIS, INDIANA, ASSIGNOR TO RAILWAY SERVICE AND SUPPLY CORPORATION, OF INDIANAPOLIS, INDIANA, A CORPORATION OF INDIANA METHOD OF RENOVATING WASTE Application filed .lune 8, 1928. Serial No. 283,772.

This invention relates to a method for renovating waste for use in the lubrication of journal boxes or in other laces,railway journal boxes, for example, eing commonly L lubricated with: such oil carrying waste.

One grave objection to the use of waste for supplying oil to the surface to be lubricated is the danger of hot boxes, due to failure of the waste to deliver the lubricant.

For some time past it has been assumed that such failures of the waste have been caused by sand, grit, or metal particles or fragments collected by the Waste during use or as part of its original composition, or by 1 short worn fibres', any of which may become compacted against the rotating surface and shield it from the lubricant. The waste was assumed to consist of 'relatively long wool and cotton fibres so completely interlaced 'as to compel travel of the lubricant in all directions and hence to the bearing, and also that these long fibres were broken or torn in use to smaller sizes having a tendency individually to lodge without motion in a given zone of the rotating surface and prevent its lubrication.

My investigation leads me to'the conclusion that more serious and harmful results are produced and many hot boxes are caused by another ingredient of the waste heretofore not taken into consideration, to wit, the lint, which is very fine textile material, either wool or cotton, or both, includingthe very fine fibres and fibrous fragments, much smailer in size than the so-called short fibres resulting from tear or wear of the longer more efiicient fibres, and which lint is both an original ingredient and is also produced by use of the waste. Under a high powered microscope magnifying twenty or more diameters a single useful strand or fibre of waste appears in the field as a heavy solid line and the lint looks like the finest hairs spreading out from the strand in all directions and of very small diameter as com pared with the strand itself. This fine lint is not firmly anchored and becomes detached and in the presence of lubricating oil during use in a journal it floats freely with the liquid toward the surface to be lubricated and ultimately niats together like felt, forming what might be referred to as an impenetrable filter bed, which blocks lubricant flow by shutting off the ability for capillary action to develop. The result is to pile up this filtering lint against the rotating journal with a failure of lubrication, rise in temperature, charring and burning of the lint and nearby oil and Waste, and the production of a tarry residue from the oil, these effects becoming cumulative until finally lubricant flow is completely shut off and a hot box develops. I have discovered that thetendency of the lint to move with the oil may be taken advantage of by using the lubricant as a vehicle to remove the lint, as will appear.

Of course, in the preparation of waste for lubricating purposes, there is no objection to removing therefrom short fibres, sand, grit, metal fragments, or other mechanical impurities from the waste during the process of reclamation or renovation thereof. Their presence is objectionable, and efiicient waste should be clean and of uniform texture. Nevertheless, according to my investigations and experience in practice the danger which dictates the removal of such materials is over-shadowed by a greater necessity for eliminating, or at least reducing, the amount of lint in renovated waste before it is supplied to a hearing, as well as its subsequent removal, should it reappear for any reason, in any later renovation or cleaning.

The oil content of waste used in lubrication is also a valuable ingredient requiring renovation, not only to remove mechanical impurities, such as grit, metal fragments and the like, chemical impurities such as soaps, pin grease, dyestuffs and the like, but also the fibrous or textile content, including lint and such short fibres as it may contain. Not only should there be renovation of the oil in the used waste as it comes to the reclaiming plant, but also, when oil is used for washing or removing impurities, partic- 95 ularly lint, from waste, such washing or cleaning oil should be also renovated to re move its lint or other harmful ingredients for the purpose of preventing impregnation of waste which is to be used by the addition [iii thereto of a lint-bearing lubricating medium.

To that end the present invention has for its object the provision of a method by which used waste may be completely renovated and the lint content therein eliminated or materially reduced, and wherein the lubricant is also renovated, particularly by the removal of lint therefrom, as well as other impurities, whereby the renovated and lintfree waste may be impregnated with usable lint-free'oil and become practically as good or better than impregnated new waste, and wherein said method may also be employed in the removal of lint from new waste to avoid carrying it to the bearing; and which method can be carried out at low cost, with simple forms of standard apparatus, and in a manner to largely do away with judgment by the operative, thereby to take advantage of low labor cost.

In the drawings, Fig. 1 is a diagrammatic view of one system or organization of apparatus for practicing the method; Fig. 2 is a detail view more or less conventionally representing an extractor; Fig. 3 is a similar view of an air cleaner; Fig. 4 is a similar view of an impregnator; and Fig. 5 is a similar view of the oil renovating unit.

Used waste, as it is delivered to a reclaiming plant, is a miscellaneous collection of various materials, including a large proportion of oil, sometimes as much as three pints of oil to a pound of waste, and also containing the lint referred to, short fibres and mechanical and chemical impurities. Generally speaking, my method contemplates a series of steps which ultimately remove from thewaste the objectionable matter, including the impurities, lint, etc., leaving a flufi'y, open mass of long usable fibres, and which reclaims the oil and, indeed, may use oil as a medium for lint removal, all oil being freed of lint and suitably renovated otherwise so that it can be re-applied' for impregnation of waste or used for any other lubricating purpose. The used'waste, as it comes to the plant, is first put into a condition in which the oil content is more or less mobile, or in other words, is readily removed from the textile fibres. For example, the used waste may be dumped into a tank or vat A, Fig. 1, where it may be heated in any suitable man ner so as to decrease the viscosity of the oil and make it mrire fluid. This tank may be a sort of kettle in which successive lots of waste are heated preparatory to the next step of the method, or it may be a large tank containing a bath of old oil maintained at a high temperature, say 180 F. and into which the waste is dumped and poled around, so that it is thoroughly heated throughout the whole mass. Some of the mechanical impurities obviously will separate and deposit in this tank and can be removed from time to time as the deposit collection increases.

The heated waste is now treated to extract the oil therefrom so as to reduce the oil cone tent to a low value. This may be accomplished in any suitable manner, such as by first draining on a rack over the tank A, if desired, and then pressing or squeezing the waste in a press patterned after the principles of a cider press or the like. However, one suitable apparatus for the purpose and which removes the oil more uniformly is a centrifugal extractor including a rotatable foraminated basket in which the waste is placed, the centrifugal action throwing off the oil into the curb, from which it drains to a suitable receptacle. By extracting the oil to a low value, either by pressing or by a centrifugal operation, a fair proportion of the lint may be removed, and, of course, the more that can be taken out in this way the better. However, some lint still remains and it is the purpose of the present invention to materially reduce the remaining lint content or even to eliminate it entirely. For this purpose, the extracted waste, preferably while still hot, is next subjected to a suitable operation to reduce its lint content. This operation may be performed by a washing operation, as it were, with the same kind of lubricating oil which is valuable in use of the waste in journal boxes or the like. The washing may be accomplished in various ways, such as in an ordinary washing machine, where the extracted waste is tumbled over and over in a bath of lint-free oil, which is drained off and removed from the waste by extraction, the oil being then treated to remove its lint content. One suitable method of washing the waste with oil involves its treatment in a centrifugal extractor. For example, the waste may be subjected to the first extraction before referred to, then taken out of the extractor basket and mixed with a mass of lint-free oil and then extracted and tial extraction referred to a quantity of lintfree lubricating oil may be poured into the extractor and caused to flow through the load of waste therein, thereby to remove lint, and may be returned again and again until the lint content of the oil is thus brought up to a maximum, or several successive and different batches of lint-free oil may be applied to the waste and extracted therefrom. One suitable method is to deliver to the waste, while in the rotating basket, a continuous stream of lint-free lubricating oil, which may be played or sprayed over the innersurface of the waste from a hose or nozzle. The drawings show a special extractor B for this purpose of the form shown in a United States patent to John W. Bercaw for centrifugal machine, granted August 28, 1928, No. 1,682,- 473, to which reference may be had for a more complete description if necessary.

, relation, the outer one being stationar and the inner one 6 being adjustably rotata le to produce more or less registration of the openings in the two cylinders, and which cylinders form a a distributor for the oil supplied to the waste by pipe 4:, centrifugalforce causing it to flow out at all levels through the registering openings in the two cylinders, which are relatively adjusted in accordance with thespeed of rotation and the viscosity of the oil, to produce the proper supply. The oil may and preferably should be heated to reduce its viscosity and increase its ability to penetrate the waste and wash out lint, if desired. The feed of oil is continued for a proper period and during the treatment the oil penetrates the waste and by centrifugal force is caused to travel through the same, taking up the lint in suspension and carryit out through the perforations or foraminations of the basket Wall. In this way practically all of the lint may be washed out of the waste. The supply of oil is now shut ofl and the extracting operation is continued to reduce the quantity of the remaining oil to a predetermined low proportlon of oil to waste, usually a lower proportion of oil than is required for eflicient lubricating purposes, so that the waste in this condition can be further treated to remove other impurities and then packaged and shipped without loss of oil in transit, although the quantity of oil may be reduced to approximately that required for proper lubricating efiiciency and after further cleaning the waste may be used just as it comes from the extractor.

In the oil flushing or washing step it is necessary to set the lint free and suspend it in the oil in a mobile condition so that it will flow with it. Experience shows that if a given batch of waste is treated with a given charge of oil and the latter is applied to the waste again and again, such as by repeated circulation, the oil body collects more and more lint until finally the proportion of lint in the oil probably reaches a maximum, after which further re-circulation or continued treatment seems to be without benefit. Oil

used totreat waste containing a small quantity of the lint might well collect a definite maximum quantity of lint from such waste by repeated circulation and find its level or stable value of lint content, but the same oil used on such waste might collect additional lint if used for treating waste containing a higher lint content. The present invention contemplates any repeated application of oil to waste, such as by re-circulation or otherwise, to a useful degree, but aims to avoid re-use of the oil for lint removal after it has collected its maximum quantity of lint under any given conditions or, in other words, to avoid any use of the lint laden oil upon waste which might permanently restore to the waste some extracted lint, the whole purpose of the invention being to remove the lint and permanently keep it out. Where to stop recirculation or repeated oil treatment depends upon several factors, such as the viscosity of the oil, its temperature, the physical character of the waste, the total lint content, the relative volume of oil bath to waste being treated, etc.

Waste ready for service in journal boxes is made up, according to the best standard, of one part of fibrous material and three parts of oil. Two parts of this oil may be considered free oil, that is, oil which is in the spaces between the fibers of the fibrous waste part. The remaining oil part is the oil film which surrounds each fiber, and makes the waste what I termfiber saturated. In other words, fifty pounds of fiber saturated waste is made up of twenty-five pounds of fibrous waste material and twenty-five pounds of oil, the oil being in the form of a film surrounding each fiber. To bring this fiber saturated waste up to a useful condition for use in journal boxes, two parts more, that is fifty pounds, of oil must be added. Therefore, one hundred pounds of waste ready for use in ournal boxes comprises or is made up of twenty-five pounds of fibrous waste material and seventy-five pounds of oil.

Two parts of the oil of the waste, namely, the free oil, may be removed by such oil removing methods as wringing, pressing or extracting, although an extractin method is the only one of the three which will remove the oil uniformly. Also the extracting method is the only one of the three which will really remove all of the two parts of free oil. The third or oil-film part can not be removed by such methods. Possibly, it could be removed by laundr washing methods, but such methods woul be injurious to the fibrouse waste material and would necessitate the use ofsome methods or some means to remove from the fibrous waste material the washing agent or agents.

I have discovered that this third or oilfilm part can be removed by a replacement method. In other words, after the two parts of free oil are removed, I can then add to the remaining fiber saturated waste a quantity of heated oil, which mixes with this third or oil-film part. By then subjecting this fiber saturated waste with this added oil to an extracting operation, a quantity of oil equal to the amount added is removed, and much of this removed oil is a part of the old oil film, which oil film has been replaced by the added oil. By one or more flushing steps as before described, this third or oilfilm part is removed, so that all of the oil of p to reduce the lint content of the waste to as a suitable gas, such low a value as possible, is not again applied to waste unless there is the possibility of removing additional lint from such Waste, but,

rather, is first suitably treated to remove its lint content and renew its lint collecting ability, or on the other hand, may sometimes be used for other industrial purposes where lint content is not objectionable. I

To enable the was-hing oil to be repeatedly flushed through a load of waste in the extractor, or in other words, to be circulated again and again, the pipe 3 may deliver the oil from the curb by way'of a valve connection 3a to a receptacle 36 from which it is returned and delivered to the extractor through pipe 4 by a suitable pump 4a, which may also be used to supply clean oil to the extractor from the oil treating plant through pipe 4, as will later appear. As stated, however, the recirculation of any batch of oil is only car ried out to a useful degree or until it has collect-ed a maximum oil content, whereupon the oil is not returned to any further waste but is permitted to flow to the oil treating plant for lint removal.

Having washed out the lint, one of the most harmful ingredients of the waste, the next step of the method is to further purify it by the removal of short fibres and other mechanical impurities, such as sand, grit, metal fragments, and the like, although in some cases this step may be omitted. This purification may be accomplished in a suitable agitating dryer, where the waste is tumbled over and over or otherwise agitated with access of drying air in any suitable manner to carry away moisture and impurities. This step may be performed by agitation in the open air, or in what is known as a drying tumbler, indicated conventionally at Fig. 1, and more or less in detail in Fig. 3. Standard machines for this purpose now on the market include a rotatable foraminous drum or cylinder 7 in which the waste is placed, and which rotates in a dryin chamber 8 through which as air, is conducted or circulated by the fan 9, the air current passing over steam heating coils 10. The machine may be of the single pass type, in which atmospheric air is conducted directly to the heating coils, then through the drum, then to the fans and out to atmosphere, or, a part of the air may be re-circulated again and again to absorb and carry away more moisture. The

waste is tumbled over and over in the drum and the mechanical impurities are shaken out and pass through the drunri openings or foraminations and are collected upon suitable screens or filtering devices or discharged to the outside atmosphere. This machine, therefore, tumbles the waste and loosens it up, separates and removes the mechanical impurities and a considerable portion if not all of the moisture, and also will remove any further lint that may have remained after the oil washing step.

Of course, all oil that comes into contact I with the waste during its renovationwill contain some lint and also may contain other impurities. That is true even though the oil be used for washing raw waste, or in other words, the product of the original shredding machine which tears the fabrics into fine fibres. Such washing may be purposely performed to free raw Waste of lint before it is impregnated with its first oil, and the oil used for its washing may be treated in the same manner as the oil now to be referred to.

The extractor shown in Fig. 2 is provided with suitable means for collecting the oil which is discharged from the curb 1 by the pipe 3. This collecting means is preferably arranged to permit separation or segregation of the original dirt-y oil from the first extraction and the later oil used for washing. The collecting means shown comprises a large tank or vessel containing two compartments, 1? and 13.- A two-way valve 14 and the branch pipes 15 enable the lubricant to be directed to either of the two compartments. The original dirty oil from the first extraction is delivered to compartment 12 which is provided with a settling chamber 16 formed by the wall 17. Oil is delivered to the chamber 16 on one side of wall 17 and is permitted to settle therein so as to deposit the heavier ingredients, the lighter and less impure oil over-flowing above the wall 17 into a second compartment 18 from which it may be withdrawn through pipe 19 either to a large collecting vessel 18a and there held for renovation, or may be directly passed to the renovating plantby the pipe 19a. Of course, the renovating plant will accommodate a relatively large quantity of oil, say one hundred gallons or so, and the oil collected from theinitial extraction of each batch of waste may be a relatively small quantity. Moreover, the oil used for washing each batch of waste and delivered into the compartment 13 will be in much larger quantity than the oil 'delivered to the compartment 12. Oompart ment 13 therefore communicates by a pipe 20 directly with the pipe 19a leading to the oil treating plant.

Renovation of the oil coming from any one or more of the aforesaid sources may be carried out in any suitable manner so long as it removes from the oil all objectionable matter, including mechanical impurities, such as sand, grit, fine metal fragments, short fibres, dyestuffs, and the like, all of the lint, the moisture, and all chemical impurities such as-soaps, pin grease, and the like. One suitable apparatus for renovating the oil is illustrated and described in United States Patent No. 1,791,474, granted February 3, 1931, to Leonard D. Grisbaum, to which reference may be had for more complete description of the process if desired. Briefly described, and as shown in the drawings, this oil renovating plant includes features as follows:

The oil to be cleaned, coming from the various places mentioned is led to a pump 21, the outlet pipe 22 of which communicates with the oil renovating plant. The latter includes three tanks, D, E and F respectively.

Tank D has a cylindrical body and conical base to the bottom of which the pipe 22 is connected. It is provided with a jacket 23 to which water may be supplied by the pipe 24 and in which jacket is a steam heating coil 25. At the top of the tank are one or morespray nozzles 26 communicating with a hot water supply pipe 27 from tank 27a. In the tank D is placed a charge of a solution of a suitable alkali, such as caustic soda. Water is supplied to the jacket and steam is passed through the heating coils 25 to raise the temperature even to a point above boiling, the water supply pipes being shut off to hold the water under pressure. The oil to be cleaned is then admitted to the bottom of the tank and bubbles up through the alkali solution, producing a sufficient agitation for the treatment. When a sufficient quantity of oid has been admitted the tank is allowed to stand for an appreciable time, say five hours, at this higher temperature. and the heating under pressure stimulates the mixing action. Finally, the valve in the water supply, which comes from the open tank 27a. is opened, relieving the pressure in the jacket and permitting the temperature to drop to approximately boiling, in which condition the tank is maintained for another period of about five hours. The cover is now removed from the tank and hot water is sprayed on the surface of the oil through the nozzles 26. This spraying is continued to thoroughly wash the oil. All soluble matter goes into solution and stays with the water. and the solid matter, including dirt particles, which may have been suspended in the oil, is carried down and settles with the sludge. The oil has the lower specific gravity and floats on the top of the water, while the sludge collects at the 7 bottom. There are now three layers in tank Dfirst, at the top there is clean oil containing traces of chemicals and water, second, the water, and third, the sludge.

The continued heating in tank D prior to the spraying or washing with water breaks down or destroys part of the lint, such as the woolen or animal fibres, and precipitates the remainder, such as cotton or vegetable fibres. It also produces chemical reactions with chemical impurities, such as soaps, grease and the like, and makes them either soluble or precipitates them. As a consequence, when the water washing step has been performed the oil in the top layer is free of lint andmechanical impurities and contains but a small portion of chemical impurities with the moisture or water in it. I

The oil in the upper layer is now drawn off through the pipe 28 and supplied thereby to a perforated pipe 29 at the bottom of tank E, which is filled with hot water. In said tank the oil rises in a greatly broken up condition and accumulates above the water level and below a hollow plate 30 heated by steam circulated through it by the pipe 31. Said plate is of hell form with a center openin or mouth and is preferably kept heated at a out 250 F. As the rising oil strikes it any water entrained in it is vaporized and escapes. Above the hollow plate 30 is a cone 32 with a. center opening 33. As the oil accumulates it finally flows out through the center opening 33 and down the sides of the cone 32 to a pipe 34 by which it is supplied to the tank F. The oil may be tested to determine its chemical content and if some chemicals still remain some clean hot water may be mixed with the oil in tank F for further washing and then drawn off through the pipe 35. In any event, the oil is supplied to tank F and permitted to collect therein by settling with the oil on top and the water at the bottom. Finally the water is drawn OE and the tank F is then heat ed by the steam coil 36 so as to vaporize and drive 011' any water by way of the pipe 37 beneath which is a baflie 38 to prevent oil loss by spattering or otherwise. This treatment dehydrates the oil and drives ofl all water, leaving a clear, clean usable oil free of chemi cals and mechanical impurities, such as lint,

Impregnation of the waste may be accomplished by what is known as an impregnator press, indicated conventionally at G, Fig. 1, and in Fig. 4, and which press, for example may be of the form shown, described an claimed in my prior United States Patent No. 1,723,747, granted August 6, 1929. Briefly described, this impregnator press includes a cylindrical tank or chamber 42 open at its top and containing a removable piston 43 capable of being drawn downwardly by the vacuum or suction efiect produced in the chamber beneath it by a source of suction communicating with a pipe 44 extending up within the chamber and entering a hollow extension 45 of the piston. The waste to be impregnated, in defi nite or measured quantity, is placed in the chamber and a proper measured quantity of oil is added to it, either above or below it. The suction effect is now applied to cause the piston to move down, all air leaving the chamber so that the oil flows into the finest interstices and crevices, not only between the fibres, but actually within them. This vacfium impregnation has the further advantage of removing any last traces of moisture that may be present, because the oil is usually hot, and the waste may also be hot, say 190 F. or so, the moisture boils off as vapor and is thereby removed. At the same time the mass is compacted and in a sense is baled and can be removed and packaged as finished lubricating waste ready for use in a journal box.

One important attribute of the invention, of course, is the removal of lint from the Waste as the result of a dry tumbling or similar operation, wherein relative motion is produced between the waste and drying air so as to carry away moisture and lint, or by flushing or washing the waste with oil, again to carry away the lint, coupled with which may be the partial or whole impregnation of the lint free waste with lubricating oil for use in v the journal, the product being a compact mass of lint-free waste containing some or all of the necessary oil, but which in any event is free from lint and therefore reduces liability of hot boxes when it is used in journal boxes for lubricating purposes. 7

What I claim is:

1. The herein described steps of a method of reclaiming used journal box packing made up of a fibrous waste part and an oil part, which steps consist of the step of placing the packing in a container; the step of appreciably reducing the oil part of the packing while said packing is in said container; the step of delivering heated oil into said container for entry into said oil reduced pack- 1ng; and the succeeding step of causing an a preciable portion of the oil then in the packing, while said packing is in said container, to forcibly pass through and out of the fibrous waste part of said packing and out of said container, the oil thus removed carrying with it at least some of the impurities of the packing.

2. The herein described steps of a method of reclaiming used journal box packing made up of a fibrous waste part and an oil part, which steps consist of the step of heating the packing; the step of placing the heated packing in a container; the step'of appreciably reducing the oil part of the heated packing while said packing is in said container; the step of delivering heated oil into said container for entry into said oil reduced packing; and the succeeding step of causing an appreciable portion of the oil then in the packing, while said packing is in said container, to forcibly pass through and out of the fibrous Waste part of said packing and out of said container, the oil thus removed carrying With it at least some of the impurities of the packing.

3. The herein described steps of a method of'reclaiming used journal box packing made up of a fibrous waste part and an oil part, said oil part being in the form of free oil and oil films surrounding the individual waste fibres, which steps consist of the step of removing from the packing as much of its oil part as possible, said step effecting the removal of the major'portion of said free oil but not the removal of said oil films; the step of adding to the oil reduced packing heated oil in acleaner condition than that of the oil removed, whereby the dirty oil of said films of reclaiming used journal box packing made up of a fibrous Waste part and an oil part, said oil part being in the form of free oil and oil films surrounding the individual waste fibres, which steps consist of the step of removing from the packing as much of its oil part as possible, said step efiecting the removal of the major'portion of said free oil but not the removal of said oil films; the step of adding to the oil reduced packing heated oil in a quantity at least as great as and in a cleaner condition than that of the oil removed, whereby the dirty oil of said films is replaced with cleaner oil; and the succeeding step of causing as much as possible of the free oil then in the packing to forcibly pass through and out of the fibrous waste part of said packing, leaving the individual waste fibres provided with oil films in a cleaner condition than those with which said waste fibres were provided prior to the step of adding said cleaner oil."

5. The herein described steps of a method of reclaiming used journal box packing made up of a fibrous waste part and an oil part, said oil part being in the form of tree oil and oil films surrounding the individual waste fibres, which steps consist of the step ofremoving from the packing an appreciable portion of its oil part, said step efiecting the removal of the major portion of said tree oil but not the removal of said oil films; the step of adding to the oil reduced packing heated oil in a quantity at least as great as and in a cleaner condition than that of the oil re- Ill moved, whereby the dirty oil of said films is replaced with cleaner oil; the succeeding step of causing the major portion of the free oil then in the packing to forcibly pass through and out of the fibrous waste part of the packing, leaving the individual waste fibres provided with oil films in a cleaner condition than those with which said waste fibres were provided prior to the step of adding said cleaner oil; and the succeeding step of adding to the oil reduced packing the desired amount of impregnating oil.

In testimony whereof I hereby atfix my signature.

EDWIN S. PEARCE. 

